The MCP boards tool answers with a `ui://forge/board` card: a board's panels as rows, with the same numbers as the page #10996

Intent: a board the owner built reads inside Claude, ChatGPT or VS Code as an MCP Apps card, the way flow, map and pull already do.

Done:

• [x] CardKind in src/web/studio/cards.ts gains board; the card shows the board's title and each panel's name and current value (at most 8 panels, then "N more")
• [x] reading one board through the boards tool names the card in its doc string, as flow does with (the ui://forge/flow card)
• [x] a test proves the card's numbers equal the page's for a fixture board, escapes a panel title with <script>, and drops private repositories' rows as the page does
• [x] bun test test/mcp-size.test.ts passes with no ceiling raised

Files: src/web/studio/cards.ts, src/http/mcp/tools/boards.ts, test/mcp-board-card.test.ts Risks: docs/MCP.md is a hot file right now, so leave it alone; the tool's doc string carries the line. Suits: scout

Reviewed pull #11040 at its head: ticked CardKind in src/web/studio/cards.ts gains board; the card shows the board's title and each panel's name and current value (at most 8 panels, then "N more"); reading one board through the boards tool names the card in its doc string, as flow does with (the ui://forge/flow card); a test proves the card's numbers equal the page's for a fixture board, escapes a panel title with <script>, and drops private repositories' rows as the page does; bun test test/mcp-size.test.ts passes with no ceiling raised.